Septic tank waste water filters require maintenance cleaning periodically. The periodic cleaning involves the removal of the filter from the septic tank in which the filter is used. For most waste water filter designs, the removal process is difficult as many gallons of waste water are held within the filter, and the filter in addition to the waste water must be lifted from the septic tank. As a result, the lifting of the filter from the tank requires two or more persons. This greatly increases the labor requirements for a cleaning procedure that would otherwise be performed by a single person. The lifting of a heavy, unwieldy filter full of waste water is possibly injurious to the maintenance personnel who are responsible for this task,
Other risks associated with the removal of waste water filters of this type is the risk of disease associated with contacting the waste water. If the filter includes waste water which will also be removed from the tank, the risks of contact with waste water, for those who will perform the maintenance cleaning procedures, greatly increase. Even if substantial precautions are undertaken to avoid contact with the waste water, the removal of waste water creates a very unpleasant situation for the maintenance personnel due to the smells produced by the waste water.
Many waste water filters further complicate the task of filter maintenance by requiring the removal of any discharge or pumping apparatus that may be disposed within the filter before the filter can be removed from the septic tank. In particular, the discharge pipe attached to a pump or dosing siphon would first have to be disassembled from the pump or dosing siphon. Thereafter, the pump or dosing siphon, along with the discharge pipe would need to be removed from the filter. After the filter maintenance is performed, the pump or dosing siphon, and the discharge pipe would need to be reinstalled within the filter. Here again, the labor costs associated with performing the cleaning maintenance are greatly increased due to this extra work. For these reasons, there is a need for a waste water filter that eliminates the need for removing the entire filter from the septic tank for simple filter element cleaning. There is a further need for a waste water filter that eliminates the need to disassemble and remove the pump and discharge pipe attached to the pump, so that simple maintenance cleaning can be performed on the filter element.
The present invention is a waste water filter for use in a septic tank. The waste water filter includes a shield comprising a vertical peripheral wall substantially impervious to the passage of unfiltered waste water. The shield further includes a top and a bottom. The shield bottom includes an opening for the entry of unfiltered waste water into the interior of the shield. A filter element is disposed substantially within the shield interior. The filter element includes a filter surface having filtering openings for restricting the passage of waste water solids of a size larger than the filtering openings, while allowing the passage of relatively clear water. The filter element further separates a first unfiltered zone within the interior of the shield from a second filtered zone within the shield interior. A reservoir within which filtered waste water may be temporarily maintained is disposed at least partially within the interior of the shield. The reservoir includes at least a first vertical peripheral wall defining a chamber which is in fluid communication with the second zone. The waste water filter further includes means to secure the reservoir to the shield, and means to secure the filter element within the shield. The filter element may be removed from the shield without the separation of the reservoir from the shield.
The first vertical peripheral wall of the reservoir may extend through the bottom of the shield. The means to secure the filter element within the shield may comprise a connection between the filter element and the reservoir. The means to secure the filter element within the shield includes means to restrict the passage of waste water solids. This connection is a typically a frictional fit between the filter element and the reservoir created through the use of a seal of deformable material. The connection is typically disposed between the bottom of the filter element and a portion of the reservoir. However, the means to secure the filter element within the shield may also comprise a connection between the filter element and the shield. Typically, this connection is also a frictional fit between the filter element and the shield created through the use of a seal of deformable material.
The reservoir may include a pump inducer chamber comprising an elongated vertical peripheral wall within which a pump may be disposed. The pump inducer chamber may be disposed at least partially within the interior of the shield, or the pump inducer chamber may be disposed at least partially outside the vertical peripheral wall of the shield.
The waste water filter of the present invention provides benefits which have not previously been available. A first benefit of the invention is derived from the independent manner that the filter element and the reservoir are disposed within the shield. By independently securing the reservoir within the shield, the filter element may be independently removed from the shield for cleaning. This ensures that cleaning of the filter surfaces of the filter element will not be avoided because of the inability or unwillingness of service personnel to lift the reservoir out of the septic tank. The lifting of the reservoir out of the septic tank is undesirable as many gallons of waste water are disposed within the reservoir. It is also undesirable to remove any waste water from within the reservoir from the septic tank. This is due to the known health risks associated with contact with waste water. Although the present invention does not ensure against contact with waste water by service personnel, the present invention clearly minimizes the likelihood of any such contact.
The manner in which the reservoir of the present invention is secured within the shield also allows a variety of filter element configurations to be used within the shield. The manner in which the reservoir of the present invention is secured within the shield is also configured so that disassembly of the reservoir from the shield is easily achieved.
The filter element may be disposed such that the top and bottom of the filter element may not move toward each other within the shield. This configuration of the filter element ensures that collapse of the filter element is not possible.